Process of sizing and quenching



Z SHEETS--SHEET l.

M. T. LOTHROP.

PROCESS 0F SIZING AND QUENCHING.

FILED fEB.5,1921.

Feb. 6, 1923.

Feb. 6, 1923. v 1,444,259. Nl. T. LOTHROP.

PROCESS 0F`S|ZING AND QUENCHING.

FILED FEB.5.1921. 2 SHEETS-SHEET 2.

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fPatentedFeb. 6, i923@ i:

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immens fr. Lorano?, or CANTON, omo, assreNoN 'ro 'ma 'tirannie normaBarrie COMPANY, or CANTON, cmo, .a coaroaa'rron or omo.

BROCESS F SIZING AND QUENCENG.

Application led February 5, 1921. Serial No. 442,737.

To all 'whom t may concern.' most position, said expanding member beingBe it known that I, MARCUS T. Lo'rHnor, shown in elevation and the coneand other a citizen of the United States, and a resident portions of theapparatus being shown in 55 of the city of Canton, in the county ofStark section;

and State of Ohio, have invented a new and F ig. 2 is a vertical sectionof the parts 0 useful Improvement in Processes of Sizing apparatusillustrated in Fig. 1, Wiith the ex' and Quenching, of which thefollowing is a panding member at the downward limit of specification.its stroke; 60

Accordingl to present practice, hardened I Fig. 3 is a view similar toFig. 1 and Fig.

metal articles of annular section, such for 4 'is a view similar to Fig.2, but with the instance, as cups and cones for roller bearexpansionme'mber shown in the form of a ings, are first shaped and sized in anysuittapering plug adapted for use in the manuable way and afterwardsheated and facture of a roller bearing cup; and 65 quenched for thepurpose of hardening Figs. 5, 6 and 7 illustrate modifications them; anddistortion is so common an inciof such apparatus suitable forrestraining dent of the hardening operation that the the cup bothinteriorly and exteliiorly durhardened article usually requires to being the quenching operation. ground to correct the distortion, notwith-`While my invention is applicable to the 70 standing that grinding isexpensive and immanufacture of' other articles, I will first depairs.the article. The principal objects of scribe it in connection with themanufacture the present invention are todevise a cheap of cones forroller bearings. and simple 'method of sizing the article, to The stock,which is preferably steel is first overcome the tendency' of thehardening opworked by ordinary metal cutting or forg- 75 eration todistort the article, and to miniing operations into a green article ofsubmize or eliminate Vthe need for grinding or stantially the sizeandshape required for like finishing operations The invention conthe finalproduct, but with its bore of slightsists principally .in making thearticle of ly smaller diametei'. This green article is green orunhardened metal of approximatethen heat treated in conformity withcurrent 80 ly the shape and size required for the finpractice or inother suitable manner; but

ished article but of vslightly smaller bore, instead of being. quenchedas it comes from heating said article, expanding the bore the furnace,it is submitted to an operation thereof to a diameter slightly iinexcess o-f that quickly stretches 'the metal circumferthat required forthe vfinished article and entially to enlarge its bore slightly inexcess 85 keepingl the bore so expanded during the of that required forthe finished product,

quenching operation. It also consistsl in and it is then immediatelyquenched without mechanically stretching the heated article releasingthe circumferential tension or and quenc-hingthe same withoutappreciable stretching force. time interval after such stretching. Italso Referring to Figs. 1 and 2 of the accom- 90 consistsln'mechanically creating circumferpanying drawing, A represents a.Agreen cone 40 ential tension in the hot article and quenchfor rollerbearings made in any suitable way ing the saniewithout relieving suchtension. but with its bore of slightly less diameter lt also-,consistsin the operations hereinafter than required for the finished article'.This described and claimed. green cone is heat treated, in accordance 95In the accompanying drawing, wherein with common or other suitablepractice; and,

like numerals refer t0 like parts wherever immediately upon its removalfrom the they occur, hardening furnace, is set on a suitable seat Fig.lV illustrates portions of apparatus 1 provided therefor on the bedplate 2 of a suitable for practicing -my process in conpress whoseplunger 3 works up and down in 10o nection with the sizing and quenchingof alinement with said sea-t.` The bed plate 2 cones for rollerbearings, such a cone 'bein-g is provided with an elongated wedge blockshown in positiondto be operated on by the 4 in axial alinementfwith theplunger and expanding member which is in its upperpreferably in the formofan upwardly tapering cone. The head of the plunger iS provided withran Vexpansion plug 5 comprising a plurality of elongatedsegmentalportions 6 which are illustrated as beingmtegral with the base of saidplug and being separated from one another by longitudinally extendingslots, T. of said segments are concentric and of the curvature requiredto produce the desired expansion of the bore of the hea-ted article;that is. the surfaces of the segments. when fully expanded radially. areconcentric with the axis of the wedge block 4 and of the plunger 3 andhave a radius slightly in excess of that desired for the finishedarticle. T he inner surfaces of said segments are tapered as illustratedat 8, and shaped to cooperate with the tapered Wedge block 4; and theparts are so related that the downward movement of the plunger Willcause the inner surfaces of said segments to bear against and be spreadradiallyJ outward by the Wedgng action of the wedge block. By thisarrangement, the hot bearing cone that surrounds the wedge block 4 andrests on the seat 1 provided therefor on the bed plate is in position topermit the expanding segments t-o entera considerable distance Iintothe. bore of the hot cone before any expanding action occurs; while thefurther downward movement of the plunger causes the segments to spread.outwardly against the inner Wall of the cone and enlarge the borethereof. As stated above. the parts should be so adjusted that. when`thesegments are fully spread. the bore of the hot cone. will be slightlygreater than that required for the finished article.

This operation of expanding the bore sets up a circumferential tensionin the metal of the cone; and it is very advantageous to quench the conewithout any appreciable interval of time after such enlargement of thebore and Without relieving the cone from the force that expanded it. Forthis reason. the quenching system is so disposed and timed segments thatthe quenching fluid is brought into operation simultaneously withcompletion of the expanding operation.

For the purpose of quenching, the seat for the hot cone is surrounded byan annular wall t) which forms with said seat a quenching well orchamber. This Wall has a multiplicity of pavssigewayys 10 extendinglongitudinally through the bottom thereof and communicating through anannularv channel 11 and a bore 12 and a pipe 13 with a source ot'quenching fluid. Each of said' passageways 10 in the Wall of thequenching Well communicates with the interior of said Well through -ietopenings 14 in the inner face of said wall: wall is provided with amultiplicity of holes 15 for draining the quenching fluid from The outersurfacesA with relation rto the expanding and the bottom portion of saidsaid Well. The supply of quenching fluidis controlled by a valve 16mounted in said bore 12 in axial alinement with the plunger/ of thepress. This valve 16, which is adapt,-

ed to move up and down, is normally seated in its uppermost position,and it is adapted` to be actuated to open position by a downwardlyextending rod 17 mounted on or movable With the head of the pressplunger in position to bear against the stem 18 of the valve and therebyopen the valve and effect the flooding of the quenching Well when theplunger approaches the downward limit of its stroke.

As the plunger moves with the usual speed of a power press plunger. theoperations of expanding and quenching the cone are accomplished veryrapidly and Without any appreciable time interval between them; and asthe jets spray the entire circumference simultaneously and While thecone is still on the expansion segments, the resulting product is freefrom distortion. As the metal is under circumferential tensionl prior toquenching, and is quenched Without releasing such tension, its bore willcontract slightly when the quenched cone is stripped from the expansionsegments. It is 011 account of this slight contraction on stripping thatthe expansion segments are set so as to expand the bore of the hot coneslightly beyond what iswa ted for the finished article.

In the case'of a roller bearing cone with an axial cylindrical bore, theshrinkage in diameter is uneven on account' of thervariation in thethickness of the Wall; and if the wall of such cone is proportionatelymuch thicker at the large end than at the small end, such unevenshrinkage will produce a -distinct taper of the bore from the narrow endof the cone towards the large end. While this taper due to shrinkage ofa Wall of uneven thickness is slight, due allowance should be madev forit in determining the taper ofthe sizing plug on which a roller bearingcone is sized and quenched; that is, the taper of such sizing plugshould be very slightly less than that desired' for the bore of thefinished cone. A similar allowance should be made also for unevenshrinkage in the case of roller bearing cups and other articles whereinlthe bore is conical and the outer surface-is approximately cylindricalor of considerably less taper than the inner surface. The effect of suchallowance is to produce aigreater enlargement of the bore at the thickend of the article, where the integrity of surface.

shape of section and reat smoothness and l istortion is eliminated,grinding of the hardened article is made unnecessary in most instances,the full depth ofthe hardened-case portion is preserved and the'surfacekis'sound and ready for use for bearing purposes.

lt is an important advantage of my process that the grinding of cups andcones for roller bearings and the like can be effected in their green orunhardened condition, as the subsequent hardening operations areeffected under 'conditions Which tend to improve rather than impair theaccuracy and soundness of the bearing surfaces. lt is noted that theprocess described not only sets up a plas/ticv flow fvvhi'ch lcauses themetal to conform accurately tothe shape of the plug or segment-s by`which it is expanded vand on Which it is quenched but that the vWithdrawal of such plug axially tends to planish or polish the surfacethereof Without impairing its soundness.

Figs. 3 and l illustrate an apparatus like that of Figs. 1. and 2, butadapted for prac- `ticing my process in connection with the sizing andquenching of ,cups for roller bearings. For this purpose, the expansionmember 'on the press plunger is not made of segmental form but is madeinthe form of a continuous plug 5a of the taper desired vfor the innersurface of the inished cup of slightly larger size than required forsuch inishedcup. For the sake of quenching, the-outer surface of saidplug is provided Witha multiplicityof longitudinally extendrooves 19.that are slightly oblique or he ical and extend to the bottom of saidplug Wherebyl said grooves communicate ywith the space 20 inthequenching Well be-,f 10W rsaid plug and thence, through a passageway 21in the seat la, With the supply 'system for the 'quenching fluid. `Theoperation of this apparatus is similar to that of the apparatusillustrated in Figs. l and 2; but it is noted that the quenching liquidis directed against both the inner and thev outer surfaces of said cup Bsimultaneously. Fig. 5 illustratesan `apparatus adapted to restrain thecup both lexteriorly and interiorly during the quenching operation.

4Said apparatus is-provided with a circular depresslon adapted to.receive the hot cup., 'llhe annular Wall of said-depression is providedWith*a series-of helical grooves 191 which communicate with thepassagevvays 10a through a series of jet openings 14a. rlhe v operationof the apparatus is similar to the operation of the apparatus shown 'inFigs. 3 and 4e; but it is noted that the cup is re- 4ing the quenchingoperation.

The apparatus illustrated in' Fig. 6 is provided"with a segmental holder23, whose outer surface .is taperedto fit the tapered seat providedtherefor in the Wall 9. The inner surface of the holder 23 is providedwith a series of helical grooves 19b which communicate through jetopenings 141 and passageways 10b with the annular channel 11. Theoperation of this apparatus is similar tothe operation of the apparatusshown in Fig. 5.

rlfhe apparatus illustrated in Fig. 7 is adapted for use in sizing andquenching cups Whose inner and outer surfaces are tapered. Saidapparatus is provided With a conical depression Whose Wall is providedwith a series of helical grooves 19 which communicate through jetopenings 14C? and passagevvays 10c' with the annular chamber 1l.

1t is noted that the apparatus hereinloe-V fore described is simplytypical and many changes may be :made-such as using solid plugsl ordiferent forms of expanding plugs from that shown and l do not,therefore, Wish to be limited to any particular form of apparatus. 1t isfurther noted that by changing the form of the plug, my process may bemade applicable to hollow articles Whose bore is not circular.

What 1 claim is: t

1. The process of treating articles of annular section which consists informing them in the green, heating them and then circumferentiallystretching the hot articles and quenching them While in stretchedcondition the operations of stretching and quenching being substantiallyinstantaneous and performed soon enough after heating to prel ventappreciable cooling of the article.

2. The" process of treating articles of annular section which consistsin forming such articles in the green, heating them and thenmechanically creating a circumferential tension in the hot articles andquenching the hot articles While still under circumferential tension theoperations of stretching and quenching being substantially instantaneousand performed soon enough after heating to prevent appreciable coolingof the article.

3.. The process of treating articles of annular section Which consistsin forming them in the green,heating them and then mechanically creatinga circumferential tension in the hot articles and immediately quenchingthem Without releasing such tension the operations of stretching andquenching being substantially instantaneous and performed soon enoughafter heating to prevent appreciable cooling ofthe article.

4. The process of treating articles of annnlar section, which consistsin forming the article in the green,.heating the same, mechanicallycircumferentially stretching the same and quenching the same while somechanically stretched and without appreciable time interval afterstretching the operations of stretching and quenching being performed sosoon after heating and so rapidly as to accomplish substantiallyinstantaneous quenching and prevent appreciable cooling of the articleprior to quenching.

5. The process of sizing and quenching articles of annular section Whichcomprises the formation of the article in the green with a slightlysmaller bore than desired f or the finished article, heating the same,circumferentially stretching the heated article to enlarge its boreslightly in excess 'of the bore desired for the finished article, andimmediately quenching the same Without releasing the circumferentialtension the operations of stretching and quenching being performed sosoon after heating and so rapidly as to accomplishsubstantially.instantaneous quenching and prevent appreciable cooling ofthe article prior to quenching.

6. The process of sizing and quenching articles of annularv sectionwhich comprises the formation of the article in the green, heating thesame, circumferentially stretching the heated article to enlarge itsbore slightly in excess of the bore desired for the finished article,and immediately quenching the same without releasing suchcircumferential stretching the operations of stretching and quenching,being substantially instantaneous and performed soon enough afterheating to prevent appreciable cooling of the article.

7. The process of sizing and quenching articles of annular section whichcomprises the formation of the article in the green With a slightlysmaller bore than desired for the finished article, heating the same,circumferentially stretching the heated article by forcing an expansionmember into the bore thereof to enlarge said bore slightly, andimmediately quenching the same While still stretched on said expansionmember the operations of stretching and quenching being substantiallyinstantaneous and performed soon enough after heating t'o preventappreciable cooling of the article.

8. The improvement in the manufacture4 of conical bearing cups and thelike which A consists in forming the same With a diameter slightly lessthan desired for the product, heat treating the same, and While stillhot forcing axially into the same a plug that has a portion of thediameter and taper desired for said product, the movement of said plugbeing continued after said portion lengages said cup to enlarge its boreslightly beyond that desired for said product.

9. The improvement in the manufacture of conical bearing cups and thelike which consists in forming the same With a diameter slightly lessthan desired for the product, heat treating the same, and while stillhot forcing axially into the same a plug that has a portion of thediameter and taper desired for said product until said portion partiallypasses its point of engagement With said cup and cooling said cup While.

.mined distance axially into a heated cup and then quenching said cupWhile inthe prep determined position on said plug, the outer surfaceofthe portion of the plug in con- .tact with said cup in saidpredetermined position being of the taper desired for said cup but ofslightly larger size.

11. The process of quenching cups for conical roller bearings whichconsists in heating said cups, restraining the same exteriorly andinteriorly in grooved conical members that fit vthe inner and outersurfaces thereof and submitting the same While so restrained to theaction of they quenching liquid introduced through the grooves, therestraining and quenching operations being so soon after heating andsorapid as to be substantially instantaneous.

12. The process of sizing and quenching articles of annular section, oneof Whose surfaces is nearly cylindrical and the other conical, whichcomprises the formation of the article in the green with a slightlysmaller bore than desired for the finished article, heating the same,circumferentially stretching the heated article to enlarge its boreslightly in excess of the bore desired for the finished article but moreat the thick end than at the thin end thereof, and immediately'quenchingthe same Without releasing the circumferential tension.

13.` rlhe improvement in the manufacture of conical bearing cups and thelike which consists in forming the same with a diameter slightly lessthan desired for the product, heat treating the same, and While stillhot forcing axially into the same a plug that has a portion of thediameter desired for said product butnof slightly less taper, themovement of said plug being continued after said portion engages saidcup tovenlarge its bore slightly beyond that desired for said product.

14. The process of making roller bearing cups and cones and the likewhich comprises the making of a green article grinding the bearingsurface thereof to approximately the size and shape of the finishedarticle, and with a smaller bore than the finished article, heattreating said article, expanding the heated article mechanically andquenching the same while mechanically reiso consists in forming the samewith a diameter slightly less than desired for the product, heattreating the same, and While still hot forcing axially into the same aplug that has aportion of the diameter and taper desired for saidproduct. I

16. The process 4of sizing and quenching cups for conical rollerbearings which consists in forcinga tapered plug a predetermineddistance axially into a heated cup and then quenching. said cup While inthe predetermined position on said plug, the outerv surface oftheportion of the plug in contact with said cup in said predeterminedposition being of the taper desired for said cup.

17. The .process of quenching cups for conical roller hearings whichconsists in heating said cups, restraining the Same interiorly on agrooved conical member that fits the inner surface thereof and submit-4ting the same While so restrained' tothe action of the quenching 'liquidintroduced through the grooves, the restraining and quenching operationsbeing so `soon after heating and so rapid as to be substantiallyinstantaneous.

18. The process of sizing and quenching articles of annular section, oneof Whose surfaces is nearly cylindrical and the other conical, whichcomprises the formation of.

the article in the green With a slightly smaller bore than desired forthe nished article, heating the same to enlarge its bore slightly inexcess of the bore desired for the finished article but more at thethick end than at the thin end thereof, and immediately quenching thesame Without releasin the circumferential tension.

igned at Canton, hiO, this 27th day of January, 1921. f

MARCUS T. LUTHROP.

